1. Field
Exemplary embodiments of the inventive concept relate generally to a DC-DC converter and a display apparatus having the DC-DC converter. More particularly, exemplary embodiments of the inventive concept relate to a DC-DC converter capable of controlling a waveform of a pulse-width modulation signal in accordance with a pattern of an image and a temperature of a display apparatus, as well as a display apparatus having the DC-DC converter.
2. Description of the Related Art
Generally, it is desirable to provide a liquid crystal display apparatus with a relatively small thickness, a relatively light weight and a relatively low power consumption so that the liquid crystal display apparatus can be used for mobile and other applications such as for a monitor, a laptop computer, a cellular phone, a television and so on. The liquid crystal display (“LCD”) apparatus includes a liquid crystal display panel configured for displaying an image using a light transmittance characteristic of a liquid crystal, and a light source apparatus. The light source apparatus provides light to the liquid crystal display panel and uses a boost converter known to be relatively stable and having a relatively high efficiency, to generate driving voltages for driving the liquid crystal display panel and the light source. The boost converter boosts the voltages for driving the liquid crystal display panel and the light source.
The boost converter may transfer information about various conditions using pulse-width modulation (“PWM”). For example, a width of a PWM signal may describe the level of voltage, a period of the PWM signal may indicate a power consumption, efficiency and compensation response time, and a slew rate of the PWM signal may indicate a power consumption and efficiency.
A conventional PWM implementation has a fixed value from a product development step onward. Thus, the PWM may not respond to a change of a particular pattern of the image, a change of a temperature and a change of a current.